1991 Ford Ranger FUEL MILEAGE

1991 FORD RANGER
104,000 MILES • 6 CYL • 4WD • MANUAL
Avatar
THEWAVE2064
  • MEMBER
  • 5 POSTS
I am only getting 11 miles to the gallon! I have replaced O2 sensor, MAFTA air flow sensor, other sensors that I can't recall at this time. At sixty-five mph it will get a slight miss( flutter ). Diagnostic test shows all sensors working but that it is running very rich(930). If you pull the vacuum cap it drops to around(3-4). I have tried Fuel Injector cleaner but hasn't made a difference. I have to fill up every 3 to 5 days and mileage is consistently
11.45 to 11.75 ( Also replaced fuel filter and air filter )
Aug 16, 2009 at 7:01 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
When was the last tune up? Also, has anyone checked to see if the catylatic converter is plugging?
Aug 16, 2009 at 8:37 PM
Avatar
THEWAVE2064
  • MEMBER
  • 5 POSTS
I had the plugs and wires replaced about 3 months ago, and the catylatic convertor replaced about the same time. The truck had 2 convertors in line, they were replaced with one ( heavy duty I guess ). All the repairs that I have told you about, sensors etc., have been made in the last 3 months. Thank you so much for your quick reply.
Aug 17, 2009 at 1:42 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Can you explain what you mean by Vacuum Cap (3 to 4)
Aug 17, 2009 at 9:33 PM
Avatar
THEWAVE2064
  • MEMBER
  • 5 POSTS


https://www.2carpros.com/forum/automotive_pictures/397234_DSC00010_1.jpg

It is the cap to the left of vac. hose to brake booster. When they pulled that cap the reading of running rich(930) dropped to ( 3 or 4 )
Aug 18, 2009 at 4:15 PM
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Sorry, I can't tell which is the booster vacuum hose. Are you refering to the rubber cap that is plugging a vacuum port? If so, that makes sense because you are allowing more fresh air to the engine. I reviewed our past posts. Has the EGR been checked to make sure it isn't plugged with carbon? I didn't see any mention of that.
Aug 18, 2009 at 10:24 PM
Avatar
THEWAVE2064
  • MEMBER
  • 5 POSTS
Honestly I do not know if it was checked.
Aug 19, 2009 at 8:01 AM
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
It is located on the intake. A vacuum line will be going to it. If you remove it, just check to make sure it isn't plugged with carbon as well as where it attaches to the intake.
Aug 19, 2009 at 6:13 PM
Avatar
THEWAVE2064
  • MEMBER
  • 5 POSTS
EGR checks out fine.
Aug 24, 2009 at 2:38 PM